A conventional steering device for a vehicle that has an airbag module, especially for a motor vehicle, includes a steering column having an extreme steering-wheel hub, to which the steering wheel is mounted. The steering wheel hub is preferably designed to be cup-shaped and includes an outlet wall having an openable cover, behind which the airbag module is disposed. The airbag module includes a gas generator and an airbag. In the activated state of the airbag module, the cover unblocks an airbag outlet, through which the airbag can be inflated in front of the steering wheel.
The covers are specifically in the form of flaps and lids, which are broken at prenotched edge slots of a cover, by a triggered airbag and the pressure building up therein, and which swing into the interior of the vehicle. In order to prevent such lids from flying uncontrollably into the passenger compartment, catch bands may be used, which restrain the flaps or lids. This manner of opening valves by means of the airbag can undesirably hinder the inflation and unfolding operation, particularly in connection with flaps that are restrained by catch bands.
Steering devices are special designs constructed in a complicated manner, so that, for example, airbag modules which are developed for an instrument panel of a vehicle, as are described, for example, in German Published Patent Application Nos. 199 31 815, 299 12 825, 197 26 878, 197 50 182 and 197 33 896, and in which a tensile force is applied to an airbag-module cover by a pyrotechnically activatable cable line to unblock an airbag outlet, cannot easily be applied to steering devices. In the case of such airbag modules developed for an instrument panel of a vehicle, one must especially consider that, in the rearward direction, i.e. in the direction of the engine compartment, there is only a small space for displacing individual component parts. In addition, the design of a steering device requires that it be constructed in an extremely compact manner since, in contrast to an instrument panel, considerably less installation space is available.
It is an object of the present invention to provide a steering device for a vehicle, especially for a motor vehicle, having an airbag module, in which the steering device can be manufactured easily and inexpensively and in which it is possible to open the cover in the region of the steering-wheel hub, in a functionally reliable and rapid manner, in order to unblock the airbag outlet.